Build crtbegin with clang too.
If _start_main is static, clang optimizes it out and then generates an
undefined reference from the inline assembler, so let's explicitly tell
the compiler it's used.
Bug: N/A
Test: ran tests
Change-Id: Iba3d9c63abae9a0dc32f236b01783515f0190956
diff --git a/libc/arch-common/bionic/crtbegin.c b/libc/arch-common/bionic/crtbegin.c
index d3a0f07..45c9ea7 100644
--- a/libc/arch-common/bionic/crtbegin.c
+++ b/libc/arch-common/bionic/crtbegin.c
@@ -30,16 +30,13 @@
#include <stddef.h>
#include <stdint.h>
-__attribute__((__section__(".preinit_array")))
-void (*__PREINIT_ARRAY__)(void) = (void (*)(void)) -1;
+#define SECTION(name) __attribute__((__section__(name)))
+SECTION(".preinit_array") void (*__PREINIT_ARRAY__)(void) = (void (*)(void)) -1;
+SECTION(".init_array") void (*__INIT_ARRAY__)(void) = (void (*)(void)) -1;
+SECTION(".fini_array") void (*__FINI_ARRAY__)(void) = (void (*)(void)) -1;
+#undef SECTION
-__attribute__((__section__(".init_array")))
-void (*__INIT_ARRAY__)(void) = (void (*)(void)) -1;
-
-__attribute__((__section__(".fini_array")))
-void (*__FINI_ARRAY__)(void) = (void (*)(void)) -1;
-
-static void _start_main(void* raw_args) {
+static void _start_main(void* raw_args) __used {
structors_array_t array;
array.preinit_array = &__PREINIT_ARRAY__;
array.init_array = &__INIT_ARRAY__;